An experimental study of competitive interference between Anigozanthos manglesii D. Don, A. humilis Lindl. and their F1 Hybrids (Haemodoraceae)

1978 ◽  
Vol 26 (6) ◽  
pp. 807 ◽  
Author(s):  
SD Hooper
Keyword(s):  
Experimental Study ◽  
Competitive Interactions ◽  
F1 Hybrids ◽  
Minor Role ◽  
Naturally Occurring ◽  
Competitive Interference ◽  
Competitive Disadvantage ◽  
Major Factors ◽  
A Minor ◽  
Hybrid Distribution

Poor competitive ability has been invoked often to explain the confinement of hybrids to disturbed ecotones at the junction of parental habitats. This hypothesis has not as yet been verified in an experimental study. Two-month-old seedlings of Anigozanthos manglesii, A, humilis and synthesized F1 hybrids were grown singly and in various paired combinations in small pots for 172 days to test for competitive interactions. F1 hybrids and A. manglesii performed comparably in most competition trials, while A. humilis suffered a considerable competitive disadvantage. It is proposed that competitive interactions may play a minor role in confining naturally occurring F1 hybrids to ecotonal areas between habitats preferentially occupied by A. humilis and A. manglesii. Spatial limitations on pollen and seed flow appear to be the major factors controlling hybrid distribution in this case.

scholarly journals Den personlige faktor: Højre- og venstreorienterede vælgere foretrækker forskellige kandidatpersonligheder

Politik ◽  
2014 ◽  
Vol 17 (3) ◽  
Author(s):  
Lasse Laustsen
Keyword(s):  
Experimental Study ◽  
Minor Role ◽  
Party Leaders ◽  
Candidate Personality ◽  
Left And Right ◽  
Student Subjects ◽  
A Minor

Candidates and party leaders are often believed to play a minor role in the party-centered Danish elections. In this article, I argue that this nding could be due to methodological as well as theoretical inadequacies. Methodologically, candidate personality needs to be disentangled from the candidates’ political positions and party a liation. eoretically, the literature on candidate personality needs to investigate the role played by ideology. Drawing on recent insights on the fundamental di erences between individuals on the ideological left and right, I argue that rightwing voters will prefer a dominant candidate personality, while their leftwing counterparts will prefer an agreeable candidate personality. e prediction is supported in an experimental study conducted on Danish student subjects. e ndings demonstrate that rightwing voters evaluate a domi- nant candidate personality more positively than leftwing voters. On the contrary, leftwing voters evaluate an agreeable candidate personality more positively than rightwing voters. e nding suggests that di erent voters prefer di erent types of candidates and that no universal winning candidate personality exists. 

Neonatal Cellular and Humoral Immunity to Group B Streptococci

PEDIATRICS ◽  
1979 ◽  
Vol 64 (5) ◽  
pp. 787-794
Author(s):  
Harry R. Hill ◽  
Ann O. Shigeoka ◽  
Robert T. Hall ◽  
Val G. Hemming
Keyword(s):  
Bacterial Infections ◽  
Metabolic Activation ◽  
Minor Role ◽  
Complement Pathway ◽  
Group B Streptococci ◽  
Opsonic Activity ◽  
Bacterial Uptake ◽  
Group B ◽  
Major Factors ◽  
A Minor

The mechanisms of host resistance to group B streptococci have not been defined precisely. In the studies reported here we have assessed the contributions of both humoral and cellular factors in protection against strains of this group. With assays of specific opsonic activity based upon the production of polymorphonuclear leukocyte chemiluminescence and radiolabeled bacterial uptake, we have demonstrated that specific heat-stable antibody and the classic complement pathway are major factors in opsonization of these organisms. In the absence of specific antibody, fresh serum resulted in markedly reduced bacterial uptake indicating, at best, a minor role for the alternative complement pathway. Additional studies have indicated that strain-specific antiphagocytic factors as well as type-specific ones may play a role in the virulence of these organisms. Neonates who developed group B streptococcal sepsis usually lacked opsonic activity in their infecting strain. In addition, polymorphonuclear leukocytes from normal term and stressed neonates showed impaired metabolic activation as measured in the chemiluminescence assay following exposure to opsonized group B streptococci. These results suggest that neonates who develop group B streptococcal disease may have defects in both the humoral and cellular aspects of their acute inflammatory response which may contribute to the high mortality observed in this most fulminant of bacterial infections.

A comparison of the sclerophyllous vegetation characteristic of Mediterranean type climates in France, California, and Southern Australia. II. Dry matter, energy, and nutrient accumulation

1969 ◽  
Vol 17 (2) ◽  
pp. 293 ◽  
Author(s):  
RL Specht
Keyword(s):  
Growth Rate ◽  
Dry Weight ◽  
Minor Role ◽  
Annual Growth Rate ◽  
North West ◽  
Phosphorus And Potassium ◽  
Major Factors ◽  
Vegetation Characteristic ◽  
A Minor ◽  
Sclerophyllous Vegetation

The annual rates of growth (on the basis of dry weight and of solar energy fixed) and nutrient uptakes of garrigue, chaparral, heath, and mallee-broombush growing in the Mediterranean type homoclime of southern France, California, and southern Australia were compared during the first 10 years of succession following fire. The Australian and Californian communities have an essentially similar growth rate of 640-2000 kg/ha/yr. The growth rate of the chaparral may be slightly greater than that of the Australian cominunities owing to greater availability of the nutrients phosphorus and potassium. The application of phosphorus fertilizer will increase the growth rate of Australian heath to that of the chaparral. Observations of Long et al. (1967) made on garrigue 10 km north of Montpellier, France indicate a growth rate of c. 1500 kg/ha/yr, essentially similar to that of the Australian and Californian communities. The author's data for a dense, vigorous stand of garrigue growing on relatively fertile calcareous soil 13 km north-west of Montpellier reveal an annual growth rate of 4000-4200 kg/ha/yr. The growth rates of these distinctive plant communities, composed of entirely different species, are largely controlled by the major factors - solar radiation and available water. In similar homocIimes essentially the same growth rate results. Within limits, soil fertility will play a minor role in controlling the growth rate and consequently the nature of the resultant plant community.

The Effect of Path Length and Display Size on Memory for Spatial Information

2012 ◽  
Vol 59 (3) ◽  
pp. 147-152 ◽  
Author(s):  
Katherine Guérard ◽  
Sébastien Tremblay
Keyword(s):  
Path Length ◽  
Potential Role ◽  
Spatial Information ◽  
Recall Performance ◽  
Minor Role ◽  
Length Effect ◽  
Serial Memory ◽  
Fixed Reference ◽  
A Minor

In serial memory for spatial information, some studies showed that recall performance suffers when the distance between successive locations increases relatively to the size of the display in which they are presented (the path length effect; e.g., Parmentier et al., 2005) but not when distance is increased by enlarging the size of the display (e.g., Smyth & Scholey, 1994). In the present study, we examined the effect of varying the absolute and relative distance between to-be-remembered items on memory for spatial information. We manipulated path length using small (15″) and large (64″) screens within the same design. In two experiments, we showed that distance was disruptive mainly when it is varied relatively to a fixed reference frame, though increasing the size of the display also had a small deleterious effect on recall. The insertion of a retention interval did not influence these effects, suggesting that rehearsal plays a minor role in mediating the effects of distance on serial spatial memory. We discuss the potential role of perceptual organization in light of the pattern of results.

Use of Different Tissue Thromboplastins in the Control of Anticoagulant-Therapy

1958 ◽  
Vol 02 (05/06) ◽  
pp. 462-480 ◽  
Author(s):  
Marc Verstraete ◽  
Patricia A. Clark ◽  
Irving S. Wright
Keyword(s):  
Prothrombin Time ◽  
Anticoagulant Therapy ◽  
Factor Vii ◽  
Rabbit Brain ◽  
Minor Role ◽  
Rabbit Lung ◽  
Coagulation Mechanism ◽  
Time Test ◽  
The One ◽  
A Minor

SummaryAn analysis of the results of prothrombin time tests with different types of thromboplastins sheds some light on the problem why the administration of coumarin is difficult to standardize in different centers. Our present ideas on the subject, based on experimental data may be summarized as follows.Several factors of the clotting mechanism are influenced by coumarin derivatives. The action of some of these factors is by-passed in the 1-stage prothrombin time test. The decrease of the prothrombin and factor VII levels may be evaluated in the 1-stage prothrombin time determination (Quick-test). The prolongation of the prothrombin times are, however, predominantly due to the decrease of factor VII activity, the prothrombin content remaining around 50 per cent of normal during an adequate anticoagulant therapy. It is unlikely that this degree of depression of prothrombin is of major significance in interfering with the coagulation mechanism in the protection against thromboembolism. It may, however, play a minor role, which has yet to be evaluated quantitatively. An exact evaluation of factor VII is, therefore, important for the guidance of anticoagulant therapy and the method of choice is the one which is most sensitive to changes in factor VII concentration. The 1-stage prothrombin time test with a rabbit lung thromboplastin seems the most suitable method because rabbit brain preparations exhibit a factor VII-like activity that is not present in rabbit lung preparations.

Produktivkraft als Versprechen

2016 ◽  
Vol 46 (185) ◽  
pp. 621-638 ◽  
Author(s):  
Christian Siefkes
Keyword(s):  
Private Consumption ◽  
Minor Role ◽  
Progressive Reduction ◽  
Internal Forces ◽  
A Minor

The ‘Fragment on Machines’ from Marx’s Grundrisse is often cited as an argument that the internal forces of capitalism will lead to its doom. But the argument that the progressive reduction of labor must doom capitalism lacks a proper foundation, as a comparison with the ‘Schemes of Reproduction’ given in Capital II shows. The latter, however, aren’t fully convincing either. In reality, more depends on the private consumption of capitalists than either model recognizes. Ultimately, most can be made of the ‘Fragment on Machines’ by reading it not as an exposure of capitalism’s internal contractions, but as a discussion of a possible communist future where labor (or work) will play but a minor role.

Effects of Myo-inositol Alone and in Combination with Seleno-Lmethionine on Cadmium-Induced Testicular Damage in Mice

2019 ◽  
Vol 12 (4) ◽  
pp. 311-323 ◽  
Author(s):  
Salvatore Benvenga ◽  
Antonio Micali ◽  
Giovanni Pallio ◽  
Roberto Vita ◽  
Consuelo Malta ◽  
...  
Keyword(s):  
Structural Changes ◽  
Natural Antioxidants ◽  
Minor Role ◽  
Positive Role ◽  
Testosterone Levels ◽  
Tnf Α ◽  
Testicular Lesions ◽  
A Minor ◽  
Immunohistochemical Analyses

Background: Cadmium (Cd) impairs gametogenesis and damages the blood-testis barrier. Objective: As the primary mechanism of Cd-induced damage is oxidative stress, the effects of two natural antioxidants, myo-inositol (MI) and seleno-L-methionine (Se), were evaluated in mice testes. Methods: Eighty-four male C57 BL/6J mice were divided into twelve groups: 0.9% NaCl (vehicle; 1 ml/kg/day i.p.); Se (0.2 mg/kg/day per os); Se (0.4 mg/kg/day per os); MI (360 mg/kg/day per os); MI plus Se (0.2 mg/kg/day); MI plus Se (0.4 mg/kg/day); CdCl2 (2 mg/kg/day i.p.) plus vehicle; CdCl2 plus MI; CdCl2 plus Se (0.2 mg/kg/day); CdCl2 plus Se (0.4 mg/kg/day); CdCl2 plus MI plus Se (0.2 mg/kg/day); and CdCl2 plus MI plus Se (0.4 mg/kg/day). After 14 days, testes were processed for biochemical, structural and immunohistochemical analyses. Results: CdCl2 increased iNOS and TNF-α expression and Malondialdehyde (MDA) levels, lowered glutathione (GSH) and testosterone, induced testicular lesions, and almost eliminated claudin-11 immunoreactivity. Se administration at 0.2 or 0.4 mg/kg significantly reduced iNOS and TNF-α expression, maintained GSH, MDA and testosterone levels, structural changes and low claudin-11 immunoreactivity. MI alone or associated with Se at 0.2 or 0.4 mg/kg significantly reduced iNOS and TNF-α expression and MDA levels, increased GSH and testosterone levels, ameliorated structural organization and increased claudin-11 patches number. Conclusion: We demonstrated a protective effect of MI, a minor role of Se and an evident positive role of the association between MI and Se on Cd-induced damages of the testis. MI alone or associated with Se might protect testes in subjects exposed to toxicants, at least to those with behavior similar to Cd.

Extraction of strontium and barium salts by the nitrobenzene solution of dicarbolide in the presence of glymes

1985 ◽  
Vol 50 (3) ◽  
pp. 581-599 ◽  
Author(s):  
Petr Vaňura ◽  
Emanuel Makrlík
Keyword(s):  
Stability Constants ◽  
Organic Phase ◽  
Equilibrium Constants ◽  
Minor Role ◽  
Nitrobenzene Solution ◽  
Ligand Structure ◽  
Stability Constants Of Complexes ◽  
Separation Factors ◽  
The Stability ◽  
A Minor

Extraction of microamounts of Sr2+ and Ba2+ (henceforth M2+) from the aqueous solutions of perchloric acid (0.0125-1.02 mol/l) by means of the nitrobenzene solutions of dicarbolide (0.004-0.05 mol/l of H+{Co(C2B9H11)2}-) was studied in the presence of monoglyme (only Ba2+), diglyme, triglyme, and tetraglyme (CH3O-(CH2-CH2O)nCH3, where n = 1, 2, 3, 4). The distribution of glyme betweeen the aqueous and organic phases, the extraction of the protonized glyme molecule HL+ together with the extraction of M2+ ion and of the glyme complex with the M2+ ion, i.e., ML2+ (where L is the molecule of glyme), were found to be the dominating reactions in the systems under study. In the systems with tri- and tetraglymes the extraction of H+ and M2+ ions solvated with two glyme molecules, i.e., the formation of HL2+ and ML22+ species, can probably play a minor role. The values of the respective equilibrium constants, of the stability constants of complexes formed in the organic phase, and the theoretical separation factors αBa/Sr were determined. The effect of the ligand structure on the values of extraction and stability constants in the organic phase is discussed.

scholarly journals The preendosomal compartment comprises distinct coated and noncoated endocytic vesicle populations.

1991 ◽  
Vol 113 (4) ◽  
pp. 731-741 ◽  
Author(s):  
S H Hansen ◽  
K Sandvig ◽  
B van Deurs
Keyword(s):  
Cell Surface ◽  
Coated Vesicles ◽  
Minor Role ◽  
Specific Marker ◽  
Con A ◽  
Early Endosomes ◽  
Gold Conjugate ◽  
Entire Cell ◽  
A Minor ◽  
Endocytic Vesicles

The transfer of molecules from the cell surface to the early endosomes is mediated by preendosomal vesicles. These vesicles, which have pinched off completely from the plasma membrane but not yet fused with endosomes, form the earliest compartment along the endocytic route. Using a new assay to distinguish between free and cell surface connected vesicle profiles, we have characterized the preedosomal compartment ultrastructurally. Our basic experimental setup was labeling of the entire cell surface at 4 degrees C with Con A-gold, warming of the cells to 37 degrees C to allow endocytosis, followed by replacing incubation medium with fixative, all within either 30 or 60 s. Then the fixed cells were incubated with anti-Con A-HRP to distinguish truly free (gold labeled) endocytic vesicles from surface-connected structures. Finally, analysis of thin (20-30 nm) serial sections and quantification of vesicle diameters were carried out. Based on this approach it is shown that the preendosomal compartment comprises both clathrin-coated and non-coated endocytic vesicles with approximately the same frequency but with distinct diameter distributions, the average noncoated vesicle being smaller (95 nm) than the average coated one (110 nm). In parallel experiments, using an anti-transferrin receptor gold-conjugate as a specific marker for clathrin-dependent endocytosis it is also shown that uncoating of coated vesicles plays only a minor role for the total frequency of noncoated vesicles. Furthermore, after perturbation of clathrin-dependent endocytosis by potassium depletion where uptake of transferrin is blocked, noncoated endocytic vesicles with Con A-gold, but not coated vesicles, exist already after 30 and 60 s. Finally, it is shown that the existence of small, free vesicles in the short-time experiments cannot be ascribed to recycling from the early endosomes.

scholarly journals Sun Protection and Sunburn in Children Aged 1–10 Years in Germany: Prevalence and Determinants

Children ◽  
2021 ◽  
Vol 8 (8) ◽  
pp. 668
Author(s):  
Tatiana Görig ◽  
Corinna Södel ◽  
Annette B. Pfahlberg ◽  
Olaf Gefeller ◽  
Eckhard W. Breitbart ◽  
...  
Keyword(s):  
Role Models ◽  
Skin Color ◽  
Role Model ◽  
Sun Protection ◽  
Minor Role ◽  
Positive Role ◽  
Protection Measures ◽  
Telephone Interviews ◽  
The Past ◽  
A Minor

Seeking shade, the use of textile sun protection and sunscreen, and protecting one’s eyes by wearing sunglasses are recommended sun protection measures in children. We aimed to quantify the use of these measures as well as the prevalence of sunburn in children aged 1 to 10 years in Germany and to identify their determinants. Data collected via telephone interviews in a nationwide sample of 554 parents or caregivers in family were analyzed. Use of sunscreen was the most common measure applied (77.8%), while sunglasses were least frequently used (12.5%). The prevalence of sunburn during the past year was 21.8%, and it was positively associated with children’s age. The use of sun protection measures was significantly associated with the age and skin color of the child, while characteristics and tanning behaviors of the caregivers only played a minor role. The use of sun protection measures was higher when caregivers perceived themselves as a role model (Odds Ratio (OR) = 4.33, p < 0.001). Our nationwide data show that there remains a need for the improved use of sun protection measures, especially in children aged 7 to 10 years. In educational material, parents should be encouraged to become positive role models for their children regarding sun protection.

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